City Tunnel (Malmö) (English Wikipedia)

"Citytunneln - Systemalternativ" (in Swedish). Archived from the original on 1 May 2010. Retrieved 6 December 2010.
"Citytunneln - Lockarp" (in Swedish). Archived from the original on 17 December 2007. Retrieved 6 December 2010.
"Citytunneln - Signalsystem" (in Swedish). Archived from the original on 2 May 2010. Retrieved 6 December 2010.
"Citytunneln - ERTMS i Citytunneln skjuts upp" (in Swedish). Archived from the original on 6 September 2009. Retrieved 6 September 2009.

jarnvag.net

"Citytunneln - Systemalternativ" (in Swedish). Archived from the original on 1 May 2010. Retrieved 6 December 2010.
"Citytunneln - Lockarp" (in Swedish). Archived from the original on 17 December 2007. Retrieved 6 December 2010.
"Citytunneln - Signalsystem" (in Swedish). Archived from the original on 2 May 2010. Retrieved 6 December 2010.
"Citytunneln - ERTMS i Citytunneln skjuts upp" (in Swedish). Archived from the original on 6 September 2009. Retrieved 6 September 2009.